Contgol assembly



June 3, 194 w. E. WHITNEY CONTROL ASSEMBLY Filed March 24, 1938 3 Sheets-Sheet 1 In ventor, M'Zlz'amll W/zz'zrze y,

June 3, 1941. w. E. WHITNEY CONTROL ASSEMBLY Filed Marcih 24, 1938 3 Sheets-Sheet 3 cA'BmET TEMP. CONTROL AUXILIARY WATER HEATER n u U Invent-071 Wz'ZZz'am if Wizz'zrze Attys.

Patented June 3, 1941 CONTROL ASSEMBLY William E. Whitney, Cambridge, Mass, assignor, by mesne assignments, to Stator Corporation, a corporation oi Rhode Island Application March 24, 1938, Serial No. 197,774

. 17 Claims. The present invention relates to an improved device for controlling the flow of fluid which is supplied under pressure and particularly to such a device for regulating the flow of gas supplied from a conventional gas main to a burner or burners. This invention in some respects presents an improved device of the general character disclosed in United States Patent No. 1,909,- 495 of Alvin S. Mancib.

The present invention provides a control as-= sembly which may be employed to particular advantage in conjunction with a combined refrigerating and water heating apparatus. Such an assembly may comprise two control chambers each of the general type disclosed in the aboveidentii'ied Mancib patent and each having a wall provided by a yieldably controlled, flexible diaphragm. Thus an arrangement is provided for regulating the pressure of the gas flowing from each chamber to a corresponding burner. In

accordance with this invention, the assembly may be provided with manually controllable shafts adapted to be adjusted by knobs on a suitable control panel. One of the control devices is adapted specifically for connection to the main burner of the refrigerating system and has appropriate control factors associated therewith to permit continued efiicient refrigeration, while the other control device is adapted specifically to be operatively associated with an auxiliary heater for supplying heat to the hot water tank I when more heat is desired than is provided by the refrigerating system. Both of the devices proved control assembly;

may have. somewhat similar control means comprising an expansible-contractible bellows and a manually operable shaft adapted to actuate eccentric means associated with a swinging control member. The eccentric means permits adjustment of the position of the control member, thus permitting modification of the influence of. the

expansible-contractiblebellows upon the control device.

The device associated with the refrigerating system is furthermore provided with additional means to facilitate defrosting of the refrigera= tor. To permit this desirable result and also to permit continuous operation of the main burner even when the food compartment is relatively cold, a suitable lay-pass is provided so that a restricted stream of gas may flow through the control chamber of the device. The control means is arranged so that the mechanism may be temporarily locked to cause the flow of gas to the main burner to be restricted, thus causin operation of that burner at a very low rate, This freezing temperature; thus permitting the device automatically to resume normal functioning.

One important aspect of the invention involves the provision of a control device provided with a valve connected to a flexible diaphragm. The device may include a valve spring or weight tending to move the valve toward its opened position, while thermostatic controlling means, (e. g., a bellows and an opposing spring) positively opposes movement of the valve toward its open position. Preferably the thermostatic controlling means is associated with rigid connecting structure extending to the valve. This structure includes a joint preventing movement of the valve relative to the controlling means in one direction, but permitting such relative movement in the opposite direction. Accordingly, when the valve can'open sufficiently to permit the pressure of the gas upon the diaphragm to balance the action of the valve spring, the valve is not under the control of the thermostatic means. Thus a definite maximum limit is provided for the rate of gas flow through the device.

In the accompanying drawings: Fig. 1 is a front elevational view of a portion of the control assembly with parts broken away, shown in section and indicated by dotted lines;

Fig. 2 is a plan view of a portion of my im- Fig. 3 is a front elevational view of the same,

with parts shown in section;

Fig. 4 is a sectional view of the control device particularly adapted for association with the refrigerating system; I

Fig. 5 is a side elevation of the device shown in Fig. 4;

Fig. 6 is a front showing the control panel; I

Fig. '1 is an end elevation of the same with certain parts shown in section;

Fig. 8 is an isometric detail; and i Fig. 9 is avertlcal section of an optional device.

Control'assemblies of the type disclosed herein are particularly adapted for use in conjunction with apparatus including arefrig erating system and water heating means in combination therewith such as the apparatus disclosed in the -copendlngapplication of Lyman F. Whitney Serial No. 192.243, filed February 24, 1938.

Such a cont-r01 assembly may ii'iclude two conelevation of the assembly trol devices associated with a common supporting means, with a common inlet pipe and, with a common safety pipe for, connection to a burner chamber, and such an assembly may also be conveniently employed in conjunction with asingle control panel arranged in a cabinet of the type disclosed in copending application No. 202,242,

filed April 15, 1938, which issued on Septemberv ,26, 1939 as United States Patent No. 2,174,299.

will first describe in detail the arrangement of the component parts of the device i.

This device comprises a lower control chamber 2 provided by a. lower casting 3. The comtrol chamber is provided with an inlet passages receiving gas from the corresponding branch of the gas supply connection t. The control chamher is also provided with an outlet passage 5 connected to a suitable line i adapted to extend to the main burner of the refrigerator. The upper wall of the control chamber 2 is provided by a flexible diaphragm t, the margin of which is clamped in place on the peripheral flange of the lowercasting 3 by a-corresponding flange of an upper casting 91 having an inverted cup-like body portion to. A valve i2 is arranged to control the flow of gas through the inlet 8 to the control chamber 2.

A tension spring it of substantial length is connected to the lower part of the valve it and to a disk 58 at the end of an externally threaded tube l9 extending downwardly from the casting 3, this tube being held in place by a nut 28! and provided with a sealing cap 2|. The spring It therefore yieldably opposes the upward movement of the diaphragm 8 and the valve I2.

This valve is provided with a body portion extending through an opening in a disk It which has a plurality of annular ribs resting upon the upper surface of the diaphragm 8, thus providing a plurality of spaced surfaces engageable with the diaphragm. Disposed over the disk It and secured to the valve-is a cylindrical connector I! having a diametrically disposed slot formed.

therein, this slot being of inverted T-shaped cross section (Fig. 8). A spindle 24 is slidably mounted in a bore in the upper part of casting 3 and has an end portion or collar 23 fitting beneath the overhanging sections of the slotted part of connector 11. The upper end of the spindle 24 is threaded and receives a nut 25 beneath a locking nut 26. An adjustable stud 44 is threaded into the upper part of the casting land is held in place by a'lock nut 49. The upa per end of the stud 44 is arranged to actas an abutment to limit the downward movement of the nut 26 and the spindle 24, thus, for example, the weight of the spindle is prevented under all operating conditions from bearing upon the connector i1 and the diaphragm 8. Accordingly, this stud a l also prevents the spindle it from imparting apositive downward thrust to the valve through connector il, it being evident that the lower end surface of the spindle is always spaced from the adjoining bottom surface of the recess in number ll.

In order to permit variation in the rate of gas flow in response to difierent temperature conditions in the food compartment of the refrigerating system or the like, a suitable expansible-contractible bellows 29, which forms part of a thermostatic means, is secured on a; bracket 30 extending upwardly from and integral with the cup-iike'portion lb of the casting 9. This bellows 29 may be connected by a flexible tube 3! to a conventional thermostatic bulb located in the vicinity of the evaporator of the refrigerating system or located at any other desired point in the food compartment. It is evident that the bellows 29, the tube 3| and the thermostatic bulb cooperate in afiording a liquid containing system arranged so that the fluidcauses expansion of the bellows. when the temperature of the food compartment rises and permits contraction of the bellows' when the food compartment temperature falls.

' In orderto aid contraction of the bellows under such conditions, a tension spring 39 is connected to the bracket 30 and to an actuating member 36. The latter may be in the form of a bell crank with the spring 33 connected to the lower 1 end ofthe depending arm thereof. This arm may be inthe form of a plate having an intermediate portion engageable by 'the end of the bellows 29, so that expansion of the bellows tends to swing the corresponding part of the bell crank 34 away from the bracket 80, while, when the pressure within the bellows is reduced, the

spring 33 tends tomove the depending arm of the bell crank in the opposite direction. The bell crank or member 34 is pivotally mounted on an eccentric portion 36 of shaft 31 and has a substantially horizontal arm with an end-portion engageable with the lower surface of the nut 25 on spindle 24. Accordingly an arrangement is provided which results in the lowering of the spindle 24 in response to expansion-oi the bellows. This permits the downward movement of the disk I4 and of the valve l2 under the into swing in a manner to lift the spindle 24 so that the latter tends to lift the valve towards its closed position.

Since the spring 39 firmly holds the bell crank 34 against the bellows 23, and since the latter. 7

preferably contains liquid and may be substantially non-compressible, the thermostatic means,

including the bellows, the spring 33 and the bell crank 34, in effect aflords a, rigid controlling system forlthe spindle M. with the connector I! in providing connecting structure between the thermostatic controlling means and the valve. The recessed portion of the connector l1 and the collar 23 at the lower end of spindle 24 afford a. one-way sl p Joint constud supportsthe weight of the spindle and the valve assembly, when the device is not connected to a gas line and when there is no superatmospheric pressure. beneath the diaphragm I. The

nectlon so that the extent of movement of the valve toward its open position under the in.- iluence oi spring I is rigidly and positively limited by the spindle 24 and the thermostatic con-' The latter cooperates V trolling means. Thus thermostatic control means is provided automatically to vary the maximum amount the valve may open in response to varying refrigerating demand. When the bellows 29 expands the spindle may gradually lower, thereby permitting the valve l2 to move downwardly under the action of spring l6.

Under these conditions the tension imposed by above the desired maximum pressure in chamber 2) when the valve moves downwardly under the tension of spring 16 as the bellows 29 expands, there comes a point where the gas pressure on 'the diaphragm 8 balances the tension of the spring and further downward movement of spindle 24 disengages collar 23' from connector l-I. When the parts are in such a position, the pressure of the gas upon diaphragm 8 is balanced by the downward pull of spring l6, so that-the device automatically functions to limit the maximum pressure in chamber 2 and the maximum rate of gas flow. It is thus evident that as thevalve 12 'moves from its closed position, it is first under the control of the thermostatic control ling means, acting through the spindle 24 and connector H, but that when the valve openssufficiently to permit the gas pressure inchamber 2 to overbalance the spring IS, the valve is removed 51 extending between front and rear brackets .58 and 59 on casting 9, and is provided with an end portion engageable in a notch till on the sleeve 50. When the shaft 36 is turned in a clockwise direction to its extreme position, corresponding to an extreme movement of the shaft 40 in an anticlockwise direction, the sleeve 50 is moved to a position permitting the end of the latch 56 to snap into engagement with the notch 50 (Fig. 4). A tension spring 60 is provided to cause such a motion of the latch. When the sleeve is in this position, the arm 54 is effective in holding the spindle 24 in a relatively elevated position so that the valve Ills closed (Fig. 4). As soon as the valve has thus been locked in its closed position, the manually controlled shaft 31 and bell crank 34 may be returned to their normal positions.

Under these conditions, gas is prevented from flowing through the inlet passage 6 into the control chamber. However, in order to avoid extinguishing the flame of the main burner, a suitable by-pass is provided to permit the flow of a restricted stream of gas into the control chamber and thence to the main burner.

being arranged in a part of the lower casting 3 to permit manual adjustment of the quantity of gas supplied through the by-pass.- A cap screw 66 from control of the thermostatic means and a maximum limit is afforded for the gas pressure in chamber land for the rate of gas flow.

Obviously, the exact point in the path of the valve where itis removed from the control of the thermostatic means depends on the pressure of the inlet gas, this point being nearer the closed position of the valve when the inlet pressure is higher. It is furthermore evident that the thermostatic means resume its control of the valve when the upper surface of collar Eli engages connector ill, due either to the upward movement of the spindle or to a reduction in inlet gas pressure.

In order to permit modification of the influence of the thermostatic means upon the rate of gas flow, a suitable manual control is provided. Such a manual control comprises a shaft M (Fig. 2)

adapted to be operated by a knob associated with a suitable control panel. This shaft it may be provided with a pinion 4i meshing with a toothed sector 62 (Fig. 3) fixed to the shaft 31. Rotation of the shaft 40 accordingly p 'mits variation in the position of the axis of the eccentric 3t about which the bell crank it swings. If this axis moves downwardly, while the pressure of the thermostatic bellows 29 doesnot change, the valve 1'2 is lowered thus permitting additional gas to flo w to the burner of the refrigerating system; 0onversely, ifthe eccentric is adjusted to lift the bell crank, less gas flows to the refrigerating systern so that the latter will tend to operate at a lower rate.

may be arranged outwardly of the screw as shown in Fig. 5.

The latch 56 is provided with an adjustable screw 89 having an end portion which may be engaged by the depending arm of the bell crank 34. Accordingly when the bellows 29 expands su-mciently, it causes the depending arm of the bell crank to engage the end of the screw 59 and to move the latter to the right, as viewed in Fig. 4, causing the latch plate 56 to move out of engagement with the notch '50. When this occurs, the spindle 2t and associated parts may fall until the nut 25 engages the upper arm of the bell crank 36, the sleeve 50 and the arm 55 meantime swinging freely on the shaft ill. Ther eupon the-device resumes functioning in the normal manner. 1

It is accordingly evident that, when it is desired to defrost the refrigerating system, the control shaft in is turned in a counter-clockwise direction to cause a clockwise movement of the shaft 31 to bring the sleeve 50 into its locked position and thus to cause the valve I2 to be held in its closed position. Thereupon the shaft M and the shaft 36 may be returned to their respective nor- I the rate of gas supply to a definite maximum.

Furthermore such a device provides a manual adjustment so that the influence of the thermostatic means upon the flow of gas may be varied,

while means is also provided to facilitate defrosting of. a refrigerator and the automatic resumption of normal refrigeration at the end of the defrosting period.

The device mi in many respects is similar to the device I, having a lower casting IN providing a control chamber I02 having an inlet I05 controlled by a valve H2 associated with a flexible diaphragm I08 supporting a disk H4 and carrying a connector H7, engageable with a col-' lar I23 of a spindle I24. .The spindle |-24 carries Such a bypass 52 is shown in Fig. 5, a suitable screw 65 I34 and an upstanding arm I59 which is pivotally mounted on a rod 294. A tension spring I99 exbell crank I34 and the upper end of the arm I56 while a spring Ifii extend-s between the lower parts of members I84 and I59. The arm I59 thus affords an abutment engaging one end of the bellows I29 and yieldably urging the end of the latter toward the depending arm of the bell crank I94.

A manually operable control shaft M9 is arranged for actuation by an exterior knob associated with the control panel. This shaft is provided with a pinion MI (Fig. 2) meshing with a toothed sector I42 mounted on the end of a shaft I31. The latter is provided with an eccentric portion I31 having a cam-like engagement with the arm I59. Accordingly when the manually actunble-shaft I49 is rotated, the shaft I9! is turned through the gear means I 4I--I42 and the Position of the arm IE9 is varied thus alterin the position of the right end of 'bellows I129, as viewed in Fig. 1. Accordingly a manually controllable adjustment is provided for the device I9I, it being evident that when the arm I56 is.

swung .to the right, as viewed in Fig. 1, the valve H2 is caused to operate before the temperature thermostatic means will cause the closing of the valve H2, thus entirely interrupting the flow of gas to the burner associated with the water heating system when the temperature of the water in the tank reaches a predetermined point. Obviously the device I9I preferably is so constructed that there is no by-pass passage corresponding tends between the intermediate portion of the t0 the passage 62 of the device I.

'The devices I and IM are secured to a common support comprising a vertical plate III with horizontal extensions II (Figs. 2 and 'l)- secured to the flanged portions of the upper and lower castings of each of the devices. Furthermore,

the brackets 59 and I99 may be secured in faceto-face relation to a metal strap 76. This strap may form the rear'wall of box-like housing 16 (Fig. 7) disposed over the u r parts of devices I and MI.

The control assembly also includes a control panel 89, shown In Figs. 6 and 7. The shafts 89 and I49 project through openings in the panel 89 and carry control knobs 49 and its, respectively. The control panel 99 may be provided with suitable indicia in the region of the knobs as shown in Fig. 6. Obviously the control panel 1 99 may be assembled with a cabinet having an opening to register therewith in th'e'general of the water in the storage tank falls so far as would be necessary for actuation of thevalve if the arm were swung further toward the left.

The eccentric I91 may provide a wide range of adjustment. In the position of the eccentric shown in Fig. 1, the device may be so adjusted that even unheated water does not cause the bellows I29 to contract sutliciently to operate valve H2. Accordingly the manual adjustment may be employed to make the booster burner inoperative, if desired.

It is to be understood that the bellows I29 is connected to atube ISI which in turn is connected to a thermostatic bulb in heat transfer relation to a part of the hot water tank. The

manner taught in the above-identified application, Serial No. 202,242, filed April 15, 1938, now United States Patent No. 2,174,299, a wall I9I of such a cabinet being shown in Fig. 7,. The panel 99 preferably is supported by the shafts 49 and I49 which are provided with compression springs 92 engaging the front wall of housing 19 and the rear face of the panel 99. Thus the springs 92 urge the panel 99 forwardly into engagement with a flange I92 on the wall I9I of the cabinet.

The upper chambers of devices I and IM also have connections with a safetyduct 99 which may extend to the housing of the main burner that is supplied with gas through the device I. Thus if there should be leakage of gas through either the diaphragm 9 or I99, the leaking gas may be directed to the main burner or the main burner stack.

Fig, 9 illustrates an optional control device provided with a control-chamber 2 having an inlet passage 5 and an outlet passage 9', tlie flow of gas from the inlet passage to the chamber being bellows, the tube, and the bulb constitute parts of a fluid containing device arranged so that anincrease in the temperature of the bulb tends to cause expansion of the bellows I29. Expansion of the bellows tends to cause the substantially horizontal arm of the bell crank 94 to swing, upwardly thus tending to lift the spindle I29 and move the valve III to its closed position against the action of spring I I9, while contraction of the bellows tends to cause opening of the valve. The control chamber I92 or the device I9! is provided with an outlet passage which is connected to a gas supply line I91 which may be connected to a' suitable booster burner or preferably may be connected to a pilot associated with such a burner and arranged to be lit by the main burner of the refrigerator in a manner fully described in the copendlng application of Lyman F. Whitney and William E. Whitney. Serial 110.192.344, filed February 24, 1938, which issued on June 6, 1939 as United States Patent No. 2,161,214. I

The thermostatic bellows I29, the bell crank I94, the lever I 89 and the spring I99 are preferably so arranged relative to each other that a substantial increase in the temperature of the control] by a valve I2. The upper wall of the chamber provided by a diaphragm 9 supporting a disk I and a connector II associated with the lower end of a spindle 24 in the same general manner as has been described. However, in this embodiment of invention the spring I9 1: omitted and 9. t "is disposed on the dish 7 I4 to afford a dowiiwordly acting force corresponding to the downward pull of the spring I6.

In this embodiment ofthe invention the externally-threaded tube I9 and the cap 2| may be omitted and a plug 92 may be threaded directly into the lower part of the casing. It is evident that a device constructed in accordance wtih the arrangement shown in Fig. Qmay be provided with cooperating factors and adjuncts similar to those disclosed in the preceding figures of the drawings, and. that theoperation of such a device is generally similar to the operation of the device previously'descrlbed, the weights 99 performing the same function as the spring I9.

It is evident that the present invention affords a convenient and effective control assembly arranged to regulate the how of gas to the burners of a household appliance such as a combined refrigerating and water-heating system. Such a device may permit automatic control of fuel flow and manual adjustment of the automatic control and may be provided with an arrangement to facilitate defrosting of the refrigerator and subsequent automatic resumption of normal operation. I

It should be understood that the present disclosure is for the purpose of illustration only and that this invention includes all modifications and equivalents which fall within the scope of the appended claims.

I claim:

1. Gas control device comprising a gas-receiving chamber having an inlet and an outlet, a diaphragm forming one wall of the chamber, a valve connected to the diaphragm and controlling the flow of gas through the chamber, means urging the valve towards its opened position, and thermostatic means including a temperature-responsive element, said element acting upon said valve rigidly and positively to oppose the action of said first-named means within a range of movement of the valve, whereby the position of thevalve in said range is determined by temperature conditions, the gas pressure in the chamber acting as the valve moves toward its opened position and is at the end of said range in r moving the valve and diaphragm from the influence 'of the thermostatic means, so that the first-named means then determines the maximum pressure within the chamber.

'2. Gas control device comprising a gas-receiving chamber having an inlet and an outlet, a diaphragm forming one wall of the chamber, a valve connected to the diaphragm and controllingthe flow of gas through the inlet, means yieldably urging the valve toward its opened position,

3. Gas control device comprising a gas-receiv ing chamber having an inlet and an outlet, a diaphragm forming one wall of the chamber, a valve connected to the diaphragm and controlling the flow of gas through the inlet, means yieldably urging the valve toward its opened position, thermostatic means including an expansible-contractible bellows and a spring tending to contract the bellows, connecting structure between the valve and the thermostatic means, the expansion of the bellows tending to result in the movement of the valve away from its closed position, said thermostatic means acting through said structure to control the position of the valve as long as the effect of the first-named means on the diaphragm more-than balances the effect of flow of gas through the inlet, means yieldably urging the valve toward its opened position, thermostatic means including an expansible-contractible bellows and a spring tending tocontract the bellows, connecting structure between the valve and the thermostatic means, the. ex

pansion of the bellows tending to result in the movement of the valve away from its closed position, said thermostatic means acting through said structure to control the position of the valve,

when the effect of the first-named means on the diaphragm more than balances the effect of gas pressure upon the diaphragm, the connecting structure being arranged so that the valve is relieved from control by the thermostatic means when gas pressure in the chamber is high enough to balance the effect of said first-named means;

means for moving the valve substantially to closed position, and a spring actuated lock thereupon automatically operative to retain the valve in substantially closed position, said lock being releasable in response to continued expansion of the bellows, thereby allowing resumption of the control of the valve by the thermostatic means.

5. A gas-control device of the class'described comprising a control chamber having an inlet and an outlet and having one wall formed by a flexible diaphragm, a valve connected to the diaphragm and controlling the flow of gas through said inlet, a thermostat for influencing the position of the valve, apa t connected to the valve, a bell crank disposed be een said thermostat and said part connected'to the valve, and eccentric means manually adjustable to vary the position of the bell crank member, thereby to vary the influence of the thermostat upon the diaphragmand the valve.

6. A control device of the class described comprising a casing including a control chamber, one

wall of which is provided by a flexible diaphragm, said chamber having an inlet and an outlet, a

valve connected to the diaphragm and regulating the flow of gas through said inlet, a spindle extending through the wall of the casing and operatively connected to said valve, abell crank member having one arm engageable with the exterior part of said spindle to vary the position thereof, an expansibie-contractible element actgas pressure upon the diaphragm, the connecting.

structure being arranged so that the valve is relieved from control by the thermostatic means when gas pressure in the chamber is high enough i to balance the effect of said first-named means."

4. Gas control device comprising a gas-receiving chamber having an inlet and an outlet, a diaphragm forming one wall of the chamber, a valve connected to the diaphragm and controlling the ing upon the other arm of the bell cranlr, a shaft providing an eccentric portion which afiords a pivot for the bell crank, said shaft being'inanually rotatable to vary the position of the bell crank and thus vary the influence of the expansible-contractible element upon the valve and diaphragm.

'7. A control device of the class described comprising a casing having a control chamber, a

finally expands to a point where it releases said means wherebythe control device resumes normal functioning.

8. A control device of the class described comprising a control chamber, a flexiblediaphragm forming one wall of the chamber, said chamber having a gas inlet and a gas outlet, a valve connected to the diaphragm and controlling the flow of gas through said chamber, a part extendingfrom said valve and having a portion outside of said chamber, an expansible-contractible element, a movable member enga'geable by said element and engaging said part to vary the position of the valve in response to the condition of said element, a manual control for varying the having a gas inlet and ages outlet, a valve connected to said diaphragm, means yieldably tending to move the valve away-from its closed position, a spindle arranged to move said valve toward closed position, a bell crank for actuating said spindle, and an expansible-contractible bellows for-varying the position of the bell crank.

10. A control device of the class described comprising a control chamber, a flexible diaphragm forming one wall of the chamber, said chamber having a gas inlet and a gas outlet, a valve connected to said diaphragm, means yieldably opposing the movement of the valve away from its closed position, a spindle arranged to move said valve toward closed position, a bell crank having an arm arranged to actuate said spindle, an expansible-contractibie element having an end arranged to move the other arm of the bell crank,

a swinging member engaging the opposite end of said element, spring means extending between said bell crank and member, and a manually controllable eccentric to vary the position orsaid member,

11. A control device of the class described comprising a control chamber, a flexible diaphragm forming one wall of the chamber, said chamber having a gas inlet and a gas outlet, a valve connected to said diaphragm, means yieldably opposing the movement of. the valve toward its closed position, a spindle arranged to move said valve towardclosed position, a bell crankhaving an arm arranged to actuate said spindle, an-expansible-contractibleelement having an end arranged to move the other arm of the bell crank,

ment to release the latch so that the valve can then move toward open position.

13. Gas control device comprising a gas-receiv-' ing'chamber having an inlet and an outlet, a diaphragm forming one wall of the chamber, a valve connected to the diaphragm and controlling the fiow ofgas through the chamber, means urging the valve toward its opened position, con trol means including a thermostatic element and acting upon said valve to oppose the action or said first-named means within a' range of movement of the valve whereby the position of the valve in said range is normally determined by temperature conditions, the gas pressure in the chamber acting as the valve moves toward its open position and is at the end of said range in removing the valve and diaphragm from the in-' licence of the control means so that the firstnamed means then determines the maximum pressure within the chamber, and a manual control for interrupting regulation of the position of the valve by the control means or by the gas pressure, said manual control being arranged to move the valve substantially to a closed position, a latch efiective to lock the valve in the lastnamed position, the control means being automatically operable in response to a relatively high temperature in releasing the latch, so that the position of the valve may thereupon be determined by the control means or by the gas pressure.

14. Gas control device comprising a gasreceiving chamber having an inlet and an outlet, a diaphragm forming one wall of the chamber, a valve connected to the diaphragm and controlling-the flow of gas through the chamber, means yieldingly urging the valve toward its open position, and control means including a temperatureresponsive element. said control means having a one way slip joint connection with the valve, said control means acting through said connection to oppose the tendency oi the first named means to openthe valve, thus permitting the positioning of the valve in various partially opened positions dependent upon the temperature of said element, the slip-Joint permitting the removal of the valve from the control 01' the control means when'the valve has opened sumciently to cause the gas pressure to balance ,th

a spring opposing. the expansible-contractible 1 element, and a manually actuable eccentric on which the bell crank is pivotally mounted, said eccentric being adjustable to vary the influence of said element upon the position of the spindle.

12. A control device oi the class described comprising a control chamber, a flexible, diaphragm forming one wall oi the chamber, said chamber having a gas inlet and a gas outlet, a valve connected to said diaphragm. means yieidably opposing the movement 01' the valve toward its closed position, a spindle arranged to move'said valve toward closed position, a bell crank having an arm. arranged to actuate said spindle, an expansible-contractible element having an end ar-- ranged to move the other arm of the bell crank, a spring opposing the expansible-contractible element, a swinging member having a part arranged to move the spindle to cause a closin eflect of said first-named means.

15. Gas control device comprising a gas receiving chamber having an inlet and an outlet, a

diaphragm forming one wall of the chamber, a valve connected to the diaphragm and controlling the fiow of gas through the chamber, means yieldingly urging the valve toward its open posi-' tion, and control means including a temperatureresponsive element, said means determining the position of the valve within a range of movement near its closed position, connecting structure disposed between said control means and said valve and including a one way slip-Joint, said means acting to-impose stress on said structure to oppose the tendency of the first named means to move th valve toward its opened position. thus permitting the positioning ofthe valve in various movement 0! the valve. a latch for said member,

and means through which the last-named arm of the bell crank maybe actuated by Said elepartially opened positions dependent upon'the temperature of the said element, the slip-joint permitting the removal of the valve from the control of the control means and the release of the connecting structure from stress when the valve has opened sufliciently tocause the gas pressure to balance theefi'ect oi'the first-named means.

16. A gas control device of the class described comprising a control chamber having an inlet v and an outlet and having one wall formed by a.

flexible diaphragm, a valve connected to the diaphragm and controlling the flow of gas through said inlet, a thermostatic device, a movable memher, said device acting through said member to vary the position of the diaphragm and valve in accordance with temperature conditions, and a flexible diaphragm, a valve connected to the diaphragm and controllingrthe flow or gas, through said inlet, a thermostatic device, a'movablemem her, said device acting through [said member to vary the position of the diaphragm and valve in accordance with temperature conditions, a control shaft carrying a toothed part, and a manshaft provided with eccentric means to vary the 1 position of the member, thereby to vary the effectiveness of the influence of the thermostatic devic on the diaphragm.

1'7. A gas control device of the class described comprising a control chamber having an inlet and an outlet and having one wall formed by a ually movable shaft carrying an inte'rmeshing part, said control shaft havllng an eccentric engageabie with said member to vary the position "WILLIAM n. WHITNEY, 

